Impacts of condensable particulate matter on atmospheric organic aerosols and fine particulate matter (PM<sub>2.5</sub>) in China
<p>Condensable particulate matter (CPM) emitted from stationary combustion and mobile sources exhibits high emissions and a large proportion of organic components. However, CPM is not generally measured when conducting emission surveys of PM in most countries, including China. Consequently, pr...
| Main Authors: | , , , , , , , , , , , , , , , , , , , |
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| Format: | Article |
| Language: | English |
| Published: |
Copernicus Publications
2022-09-01
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| Series: | Atmospheric Chemistry and Physics |
| Online Access: | https://acp.copernicus.org/articles/22/11845/2022/acp-22-11845-2022.pdf |
| Summary: | <p>Condensable particulate matter (CPM) emitted from stationary combustion and
mobile sources exhibits high emissions and a large proportion of organic
components. However, CPM is not generally measured when conducting emission
surveys of PM in most countries, including China. Consequently, previous
emission inventories have not included emission rates for CPM. Here, we
construct an emission inventory of CPM in China with a focus on organic
aerosols (OAs) based on collected CPM emission information. Results show that
OA emissions are enhanced twofold after the inclusion of CPM in a new
inventory for China for the years 2014 and 2017. Considering organic CPM emissions and
model representations of secondary OA (SOA) formation from CPM, a
series of sensitivity cases have been simulated here using the three-dimensional
Community Multiscale Air Quality (CMAQ) model to estimate the contributions
of CPM emissions to atmospheric OA and fine PM (PM<span class="inline-formula"><sub>2.5</sub></span>, particulate matter with
aerodynamic diameter not exceeding 2.5 <span class="inline-formula">µ</span>m) concentrations
in China. Compared with observations at a Beijing site during a haze episode from 14 October
to 14 November 2014, estimates of the temporal average
primary OA (POA) and SOA concentrations were greatly improved after including
the CPM effects. These scenarios demonstrated the significant contributions
of CPM emissions from stationary combustion and mobile sources to the POA (51 %–85 %), SOA (42 %–58 %), and total OA
concentrations (45 %–75 %). Furthermore, the contributions of
CPM emissions to total OA concentrations were demonstrated over the 2 major
cities and 26 other cities of the Beijing–Tianjin–Hebei region (hereafter referred to as the “BTH2 <span class="inline-formula">+</span> 26 cities”) in December 2018, with average contributions of up to 49 %, 53 %, 54 %, and 50 %
for Handan, Shijiazhuang, Xingtai, and Dezhou, respectively.
Correspondingly, the inclusion of CPM emissions also narrowed the gap
between simulated and observed PM<span class="inline-formula"><sub>2.5</sub></span> concentrations over the BTH2 <span class="inline-formula">+</span> 26
cities. These results improve the simulation performance of atmospheric OA
and PM<span class="inline-formula"><sub>2.5</sub></span> and may also provide important implications for the sources of
OA.</p> |
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| ISSN: | 1680-7316 1680-7324 |